The installation of slate and tile roofs is labor intensive and typically requires skilled workers to properly set down overlapping courses of relatively brittle roofing tiles. When used herein, “tiles” refers to natural tiles such as slate tiles as well as artificial tiles such as those fabricated from ceramic materials.
Recent developments in slate roof installation systems have simplified the installation of roofing tiles while also reducing the amount of tiles required to cover a roof. One such improved system requires only a single overlap of one upper course or row of tiles over the top or upper portion of a lower course of tiles. This system requires the use of a layer of water resistant material such as a thin sheet of plastic, “tar paper” or similar construction material to provide adequate protection for the underlying roof decking.
That is, instead of using three rows of overlapping tiles to waterproof an underlying roof deck, a layer of waterproof or water resistant sheet material is placed beneath each row of tiles so as to provide a water repelling layer beneath the adjacent side edges of adjoining tiles. The sheet material thereby prevents water seeping between the cracks or openings formed between adjacent tiles from damaging the underlying roof deck.
While this system is easier to install than conventional “three layer” tile roofs, the underlying layers of water resistant material can degrade over time due to embrittlement from sunlight as well as from abrasion from sand, dust and grit particles blown by high winds. Moreover, the lowest course or row of tiles in “two layer” systems can be subject to damage from high winds due to the lighter weight of a single overlying row of tiles.
That is, conventional three layer tile roofs apply the weight and stability of two overlying courses or rows of tiles to the lowest or bottom row or course of tiles to secure each respective bottom row of tiles in position. This is particularly advantageous along the lowest row or course of tiles located along eave portions of each roof where exposure to high winds tends to lift or peel the exposed tile edges upwardly, allowing for the entry of wind-blown rain. In extreme conditions such as in hurricanes, these eave tiles can be lifted upwardly and blown away.
This disclosure is directed to lightweight tile roofing systems which address the drawbacks noted above. In particular, in one embodiment, a tile roofing system is disclosed wherein a single overlap between two rows of tiles is strengthened along the lowest row of tiles adjacent the eave of a roof.
Moreover, the portion of a waterproofing layer of sheet material exposed between the cracks or openings formed between the sides of adjacent tiles is protected with an overlying strip of water resistant or waterproof material, such as high density polyethylene (HDPE).